Train-carried receiver for automatic train-control systems



Sept.

H. O. HOLTE TRAIN CARRIED, RECEIVER FOR AUTOMATIC TRAIN CONTROL SYSTEMSFiled March 1926 2 Sheets-Sheet 1 lllllllllllllllllr. ll lllllllllll vfl v I l I l I I l I l II I l I I i-\\ N: L k. 7% .n v m N RN mm JQNR.Kl. Ma Q Q SAW T Y i? Rig WT M Q E 3 M A 6M mm MHHPH UHHHHHHU I R%llhHll I I l I I I I l I l. l I I a I I I l l I I I I l lllvklllllnl v Qum MN AJ l i m m N N m 3 RN l l l I I l l l ll Illlllllllb.

V 1,643,377 p 1927- H. o. HOLTE TRAIN CARRIED RECEIVER FOR AUTOMATICTRAIN CONTROL SYSTEMS Filed March 1926 2 Sheets-Sheet 2 I I I .111: III.

3Q INVENTORT 4 N.@-Ml N @Q-i-W D Patented Sept. 27, 1927.

UNITED STATES PAT N oFricE.

HAROLD o. HOLTE, orrlr'rseuneii, PENNSYLVANIA; HALvoRnoLTE, SPECIAL AD-ivimrsrimron or SAID HAROLD o. HOLTE, DECEASED, ASSIGNOR 'ro' 'rnn"UNIG'N SVTITCH & SIGNAL centenary, .OF reimsvrivanm, A CURPORATION OFPENNSYLVANIA.

TRAIN-CARRIED RECEIVER FORAUTOD'IATIC TRAIN-CONTROL SYSTEMS.-

Application filed March 19, 1926. SeTial No. 95,922

My invention relates to automatic'train control systems of the typewherein train carried apparatus is controlled at least in part byalternating train controlling currents which flow through the tracl;rails. More specifically, my present invention relates to train carriedreceivers for use in systems of this character.

One object of my invention is the provision of a receiver which willsupply energy to the train carried apparatus in accordance with thetrain controlling current in the rails, but which will not supply energyto such apparatus in accordance with alternating currents flowing in adacent transmission lines orin adjacent tracks, etc.

I will describe two forms of receivers embodying my invention, and willthen point out the novel features thereot n claims.

1n the accompanying drawings, Fig. 1 is a view, partly diagrammatic,showing one form of train carried receiver embodying my invention. Fig.2 is a view illustrating one modification of the receiver shown in Fig.1 and also embodying my invention. Fig-s. 3 and at are views showing,intop plan and front elevation, respectively, the com plete receiver Aillustrated diagrammatically in Figs 1 and 2. Fig. 5 1s. a diagrammaticview showing a portion of an automatic train control system includingreceivers embodying my invention.

Similar reference characters refer to similar parts in each of theseveral views.

Referring first to Fig. 5, the reference characters 1 and 1 designatethe track rails of a railway, which rails are divided by insulatedjoints 2 to form a track section. Connected across the rails of thissection at spaced points are two resistances 8 and S, and connected withthe middle points of these tworesistances, respectively, are the twoterminals of the secondary 7 of a loop transformer T. The primary 6 ofthis transformer is supplied with alternating train controlling currentfrom a suitable source not shown i i-thedrawing. It will be apparentthatthe current supplied by.

transformer T. flows through, .the twotraclt r s 1 and 1 in multiple,that 1S,.1i7 any instant, it flows in the same direction in thetworails. I shall call tli6,t1 2111i controlling current time. suppliedto the trackway loop current. v l I i Means are alsovprovided forsupplying track circuit current to the rails of the track sect on.former, designated by'the reference character J has its secondary 4connected across the rails adjacent one end'of the section. The primary5 of transformer J is constant ly supplied with alternating current froma suitable source not shown in the drawing. The track circuit currentsupplied to the rails by transformer J may be used to control governingmeans of any suitable form which may include a track relay Q, connectedacross the rails adjacent the opposite end of the section. v The trackcircuit current supplied to the rails by transformer J flows through therails 1 and 1 in opposite dii'ections at any given instant.

The reference character W designates a railway train provided withreceivers A and A embodying my invention. Referring to Fig. 1,'receiverA. comprises a member S of magnetizable material extending transverselyacross the two track rails 1 and l and made up of three sections, 8, 9and 10. The ends of sections 8 and 9 are separated'by an air gap 14',and sections 9 and-lO'are spaced apart by an air gap 15. The receiver Acomprises also four downwardly projecting legs, 16, 17, Y18, and 19, sodisposed that the legs'16 and 17 are on opposite sides of one track rail1 and the legs 18 and 19 are on opposite sides of the other trackrail 1. Legs 17 and 18 are spaced from the ends of section 9 of member Sby air gaps 25 and 26,- respectively. In similar fashion .leg 16 isspaced fromsection 8 by air gap 24, and leg 19. is spaced from section10 by an air gap 27. Legs: 17 and 18 are provided with feet 28 and 29spaced fromthe correspond ing legs by air gaps 30 and 31 respectively,and extending in direction parallel to the track rails as best shown inFig. .5. The four legs 16, 17, 18 and 19 carry a winding which is madeup of four coils 20.21, 22 and 23 located upon the four legs,respectively. This winding is included in .a'piclc up circuit, .3 andsince the receiver illusiii ed in Fig. l'is intended to supply currentto For this purpose a track trans-- the train carried apparatus inaccordance with the 100 current in the trackway, the four coils. o thereceiver are connected in series in the pick-up circuit in such mannerthat the polarities of the coils on each two adjacent legs are opposite.The pick-up circuit'also includes a condenser38 which will usually beadjusted to balance the inductive reactanceof the circuit B, so that thecircuit is tuned to resonance at the frequency of the loop currentsupplied to. the track rails: from transformer T.

The pick-up circuit B may be used in connection with train carriedgoverning apparatus, of any suitable type. As here' shown this circuitsupplies energy to one wind ng 2 39 of an induction, motor relay R,theother tions as to create electromotive forces in the circuit B which areadditive. Similarly, the flux 86 surrounding rail 1 will flow throughcoils 20 and 21 in such directions as to create electromotive forces inthe circuit B which are additive.v Furthermore, the electromotlve forcesthus created in coils 20 and 21 by the one flax and in coils 22 and 23theother flux are additive. An electromotive force is therefore createdacross the terminals of condenser 3.8 due to the loop current flowing inthe track rails.

The two rails will also be surrounded by a magnetic flux which maly berepresented by the broken line 37. is flux will flow through the coils20 and 23 in such direc-,

tions as to create electromotive forcesin these C0115 which areadditive. to each other'and which are also additive to theelect-romotive forces created by fluxes 36 and 36 surrounding theindividual track rails.

"A horizontal foreign magnetic flux will pass partly along the member Sand so will create no electromotive force in the windings of receiver A.In order to increase the proportion of the foreign flux which traverses.this path through the receiver, I provide arms 12 and 13 which projectfrom. the. ends of the member S. Another part. of such foreignhorizontal flux will enter the receiver at leg 16 and will leave at leg19, whereas still another part will enter at leg 1'? and leave at leg18. These two last mentioned parts of the foreign flux will createopposite electromotive forces in the circuit B,

and by proper proportioning of the number of turns in the several coilsand of the size of the feet 28 and 29, these. two opposite electromotiveforces can be made approximately equal so that they will have no effectupon the relay R. The foreign flux throu h the legs of the receiver isdecreased by the air 'gapsfld, 2'5, 26 and 27 and also by the air gaps30' and 31. The air aps-1 1 and 15 cause a v greater proportion of thehorizontal foreign flux to traverse legs 17 and 18 than would otherwisebe thecase. But these two air gaps also decrease the effectiveness ofthe receiver in its response to loop current in the trackway and I havediscovered that there is an optimum length for these air gaps for anygiven receiver. In the form shown in thedrawing' each of the sections 8,9 and 10 of member S is 27 inches long, and each of the legslfi, 17, 18and 19 is 5 inches lon For a receiver having these proportions, havediscovered that the optimum length for the air gaps 14 and 15 is.06inches.

The four air gaps 30, 25, 26 and 31 should 7 be as small as possible andmay, for example, be .01 inches. The length of each air gap 2 1 and 27is preferably .015 inches.

WVith the receiver proportioned as just described I have found'that ifthe ratio of the turns in coils 21 and 22 to theturns in coils 20 and 23is 5* to 8, a uniform foreign l1orizontal flux will have substantially.no. upon the pickup circuit B.

A vertical foreign flux will pass through all four legs of the receiverin the same direction, and the resulting electromotive forces induced inwindings 20 and 21 are balanced by the electromotive forces induced inwindings 23 and 22, respectively, so that the net elfechof this verticalflux upon the pick-up circuit is substantially nil. It follows from theforegoing that any foreign magnetic flux due to alternating current in atransmission line or an adjacent track will create little or noelectromotive effect force in thepick up circuit B, and so will havelittlev or no tendency to cause false operation of the train governingrelay R.

In a train control system of the type to which this invention relates,the receiver A is usually located between the engine and the tender ofa. steam train, and between the first and second car of an electrictrain. I have found that in some instances aportion of the loop. currentfrom transformer T will leave the rails-at the forward end of the train,pass through the steel construction and couplers of the train, andreturn to the rails at the rear end of the. train. Inasmuch as thereceiver A is usually located under the coupler, it follows that thiscurrent llU which passes through the train itself, and V which isusually termed the coupler current, will pass above the receiver A. Whenthe receiver 1s constructed 1n accordance with my invention, themagnetic flux surrounding the coupler will pass largely through themiddle legs 17 and 18 of the receiver and so will create electromotiveforces in the coils 21 and 22 which assist the electromotive forcesinduced in these coils by the current which remains in the track rails.

The various parts of the receiver may conveniently be assembled as shownin Figs. 3 and 4.

Referring to these views, the sections 8, 9 and 10 of the niember S aremountedbe, tween members 11 and 11 which extend the entire length of thereceiver. The members 11 and 11 are clamped together by a num ber ofsplit housings 32, 33,34 and 35, which housings surround'legs 16, 17, 18and 19 respectively and hold the legs in fixed positions with respect tothe member S, These housings have the further function of protectingfrom the elements the coils which are placed upon these legs. The arms12 and 13 are clamped in place by the housings 32 and 35.. A bolt 41passes through leg 17 and section 9 of bar S and is provided with a nut11* to hold foot 28 in its proper position. Similarly foot 29 is held inplace by a. bolt 42 passing through leg 18 and section 9 and. providedwith a nut 42*. I refer to make the members 11 and 11" of cold rolledsteel and the housings 32,33, etc., of cast aluminum. It will thereforebe seen that parallel magnetic paths are provided around the air gaps ofthe receiver. I prefer, however, to construct the sections 8, 9,

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10 and the legs 16, 17, etc., of laminated soft iron so thatsubstantially all the flux passes through these parts of greaterpermeability and the members 11 and 11 and the housings 32, 33, etc.,have substantially no tendency to interfere with the described effect ofthe air gap. It is manifest that with the receiver assembled as shown inthe drawing the various parts can be permanently clamped in their properpositions so that the lengths of the air gaps have the required values.

Under some conditions of operation it is desirable to operate the relayR in accordance with the track circuit current, that is, the currentsupplied by transformer J in Fig. 1, instead of the loop currentsupplied by transformer T. With a receiver embodying my invention thiscanbe accomplished by the simple expedient of inverting the coilsassociated with one rail. For example, as shown in Fig. 2 the receiveris similar to that shown in Fig. 1 except that coils 22 and 23 have beeninverted. The flux 36 surrounding rail 1 passes through legs 16 and 17and creates in coils 20 and 21 electromotive forces which are additive.The flux 36 surrounding rail 1 creates in coils 22 and 23 electromotiveforces which are additive to each other and which are also additive tothe electromotive forces created in coils 20 and21 by flux 36. l/Vinding10 of relay R is supplied with cur rent in accordance with the trackcircuit current supplied to the track rails land 1. A horizontal foreignflux will pass partly through the member S as explained herein.. before,and this part of the flux will have no effect upon the receiver winding.Another part of this horizontal flux will enter the receiver at leg 16and will leave at leg 19. Still another part of the foreign flux willenter at leg 17 and leave at leg 18. The part of the foreign flux which?passes through legs 16 and 19'will induce in coilsv 20 and 23electromotive forces'which are in opposition to the electromotive forces1n duced in coils 21 and 22 by the part of the foreign flux which passesthrough legs 17 and 18. p

Furthermore a vertical foreign flux will pass through all the coils inthe same direc tion an; the clectromotive forces created by thisfoieignflux in coils 20 and 23 will op pose the elcctromotive forces created bythis vertical foreign flux in coils 21 and 22. By properly proportioningthe various parts I have discovered that the receiver can be madesubstantially immune tothe effect of any foreign flux. W'ith themagnetic structure shown in the drawing which is the same as that shownin Fig. 1, the ratio of turns in coils 21 and 22 'to the turns in coils20 and 23 is 7 to 4 for the receiver of Fig. 2.; With the partsproportioned in this manner similar receivers may be used withthe sameturn ratios for receivingtrack circuit current when the coils areconnected as shown in Fig. 2, and for receiving loop current when thecoils are connected as shown in Fig. 1. In either case foreign flux willhave substantially no effect upon the pick-up circuit 13. g at.

Although I have herein. shown and de scribed only two forms of traincarried receivers for automatic train control systems embodying myinvention, it is understood, that various changes and modifications maybe made therein within the scope of the appended claims withoutdeparting from the spirit and scope of my invention.

Having hus described my invention, what I claim is: i

1. A train carried receiver comprising a member extending transverselyacross the track rails and having four downwardly projecting legseachspaced from said member by a small air gap, and a winding made up of acoil on each leg, said coils being connected in series in such mannerthat the electromotive forces induced therein by 2.1

ternating currents in the track ditive.

2. train carried receiver comprising a rails are ad:

track rails and iaving four downwardly projecting legs each spaced fromsaid; Inc-1n any a sn iall air gap and two of such air gaps beingoidifferent length from the reinaini'ng air-gaps, and a winding made up ofa coil on each. leg, said coilsbeing con nected in series in such mannerthat the polarities of the coils on each two adjacent legs are opposite.

' 4. A train carried receiver comprising a member extending transverselyacross the track rails and having four downwardly projecting legs, twomagnetizable arms tached to the upper side out said member and extendingoutwardly from the ends thereof, and a winding made up of a coil on eachsaid le said coils being connected in series.

it A train carried receiver comprising a memberextending transverselyacross the track rails. and made up of three sections separated by airgaps, two legs downwardly projecting from the outer ends of the twoouter sections, respectively, two legs downwardly projecting from theends of the middle section, and a winding made up of a coil on each ofsaid legs, said coils being connccted in series. i

6. A train carried receiver comprising a member extending transverselyacross the track rails and made up of a middle section and two outersections separated by airgaps, two legs one projecting downwardly fromthe outer end of each said outer section and each spaced from theassociated section by an air gap oi" one length, two other legsprojecting downwardly from the ends of said middle section and separatedtherefrom by air gaps of a dill'erent length, and a winding made up of acoil on each said leg, said coils being connected in series.

7. A train carried receiver comprising a member extending transverselyacross the track rails and made up of a middle section and two outersections separated by air gaps, two legs one projecting downwardly fromthe outer end of each said outer section and each spaced from theassociated section by an air gap of one length, two other legsprojecting downwardly from the ends of said middlesection and separatedtherefrom by air gaps of a different length, two feet one depending fromeach of said last-mentioned meant":

each spaced from the associated section by a an air gap, two otherlegsprojecti-ng downwardly from the ends of said middle section and eachprovlded at its lower end with a foot having a greater length inadirection. parallel to the track rails than 'the correspondingdimensiono-f the associated leg, and a winding made up oi four coilsone: on each said leg, said coils having diflerent numbers of turns. 1 i5 9. A train carried receivencomprising a member extendingtransverselyacross the track rails and made upof amiddle section and twoouter section-s separated by air gaps, I

two legs, one projecting downwardly the outer endof eachsaid outersection. and eachspaced irom the associated section by an air gap,twoother legs projecting downwardly from the ends of' said middle sectionand each providedat its lower end with a foot having agreaterlengtlr ina direction pa allel to the track rails than the correspondln dnnensionof the associated leg, and a winding made up of four coils one on eachsaid leg all connected in series and the coils on the twofirst-mentioned legs having a smaller numberof turns than the coils on vthe 'remainmg legs.

10 A train carried receiver comprising a member; extending transverselyacross the track rails and made up of a middle section and twooutersections separated by air gaps, two legs, one pro1ectitngdownwardly from the outer'end of each said outer section and each-spacedfrom the associated section by an air gap, two other legs projectingdownwardly iromjthe ends of said middle section and each provided at itslower end with a, foot having a greater length in a direction parallelto the track rails than the corresponding dimension of the associatedleg, and a wlnding made up of four coils oneon each leg all connected inseries and the ratio of the turns in thecoils on thetwofirst-niexitioned legs to the turns in the coils on the ast-mentionedlegs being substantially 5 to 8. v a

11. A train carried receiver comprising a, member extending transverselyacross the track rails and made up of a middle section and two outersections each substantially twenty-seven and one-half incheslongseparated by air gaps of substantially .06 inches,

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two legs, each substantially five inches long and one projectingdownwardly from the outer end of each said outer section and spacedtherefrom by an air gap of substantially .015 inches, two other legseach substantially five inches long projecting downwardly from the twoends respectively of said middle section, and a winding made up of fourcoils one on each leg, said coils being connected in series in suchmanner that the electromotive forces induced therein by alternatingcurrents flowing in the track rails are additive.

12. A train carried receiver comprising a member extending transverselyacross the track rails and made up of a middle section and two outersections each substantially twenty-seven and one-half inches longseparated by air gaps of substantially .06 inches,

two legs, each substantially five inches long and one projectingdownwardly from the outer end of each said outer section and spacedtherefrom by an air gap of substan tially .015 inches, two other legseach substantially five inches long projecting downwardly from the twoends respectlvely of said middle section, and each provided at its lowerend with a foot having a greater length in a direction parallel to thetrack rails than the corresponding dimension of the associated leg, anda winding made up of four coils one on each leg, said coils beingconnected in series and the ratio of the turns in the coils on the twofirst-mentioned legs to the turns in the coils on the remaining legsbeing substantially 5 to 8.

In testimony whereof I affix my signature.

HAROLD O. HOLTE.

